須田 康一

BACKGROUND: Although the da Vinci™ Surgical System is the most predominantly used surgical robot worldwide, other surgical robots are being developed. The Japanese surgical robot hinotori™ Surgical Robot System was launched and approved for clinical use in Japan in November 2022. We performed the first robotic gastrectomy for gastric cancer using hinotori in the world. Here, we report our initial experience and evaluation of the feasibility and safety of robotic gastrectomy for gastric cancer using hinotori. METHODS: A single-institution retrospective study was conducted. Between November 2022 and October 2023, 24 patients with gastric cancer underwent robotic gastrectomy with hinotori. Five ports, including one for an assistant, were placed in the upper abdomen, and gastric resection with standard lymphadenectomy and intracorporeal reconstruction were performed. The primary endpoint was the postoperative complication rate within 30 days after surgery. The secondary outcomes were surgical outcomes, including intraoperative adverse events, operative time, blood loss, and the number of dissected nodes. RESULTS: Of the 24 patients, 16 (66.7%) were male. The median age and body mass index were 73.5 years and 22.9 kg/m2, respectively. Twenty-three patients (95.8%) had tumors in the middle to lower stomach. Sixteen (66.7%) and seven (29.2%) patients had clinical stage I and II diseases, respectively. Twenty-three (95.8%) patients underwent distal gastrectomy. No patient had postoperative complications of Clavien-Dindo classification IIIa or higher, whereas two (8.3%) had the grade II complications (enteritis and pneumonia). No intraoperative adverse events, including conversion to other approaches, were observed. All patients received R0 resection. The median operative and console times were 400 and 305 min, respectively. The median blood loss was 14.5 mL, and the number of lymph nodes dissected was 51.5. CONCLUSIONS: This study found that robotic gastrectomy with standard lymphadenectomy for gastric cancer using hinotori can be safely performed.

BACKGROUND: This study aimed to determine the safety and feasibility of minimally invasive gastrectomy in patients who underwent preoperative chemotherapy for highly advanced gastric cancer. METHODS: Preoperative chemotherapy was indicated for patients with advanced large tumors (≥ cT3 and ≥ 5 cm) and/or bulky node metastasis (≥ 3 cm × 1 or ≥ 1.5 cm × 2). Between January 2009 and March 2022, 150 patients underwent preoperative chemotherapy followed by gastrectomy with R0 resection, including conversion surgery (robotic, 62; laparoscopic, 88). The outcomes of these patients were retrospectively examined. RESULTS: Among them, 41 and 47 patients had stage IV disease and underwent splenectomy, respectively. Regarding operative outcomes, operative time was 475 min, blood loss was 72 g, morbidity (grade ≥ 3a) rate was 12%, local complication rate was 10.7%, and postoperative hospital stay was 14 days (Interquartile range: 11-18 days). Fifty patients (33.3%) achieved grade ≥ 2 histological responses. Regarding resection types, total/proximal gastrectomy plus splenectomy (29.8%) was associated with significantly higher morbidity than other types (distal gastrectomy, 3.2%; total/proximal gastrectomy, 4.9%; P < 0.001). Specifically, among splenectomy cases, the rate of postoperative complications associated with the laparoscopic approach was significantly higher than that associated with the robotic approach (40.0% vs. 0%, P = 0.009). In the multivariate analysis, splenectomy was an independent risk factor for postoperative complications [odds ratio, 8.574; 95% confidence interval (CI), 2.584-28.443; P < 0.001]. CONCLUSIONS: Minimally invasive gastrectomy following preoperative chemotherapy was feasible and safe for patients with highly advanced gastric cancer. Robotic gastrectomy may improve surgical safety, particularly in the case of total/proximal gastrectomy combined with splenectomy.

BACKGROUND: Hydrocele of the canal of Nuck (HCN) is a rare disease, and its indications for laparoscopic surgery are not well-established. CASE PRESENTATION: A 53-year-old woman was referred to our hospital due to an uncomfortable thumb-sized inguinal mass. Preoperative computed tomography scan and magnetic resonance imaging revealed a hydrocele extending from the abdominal cavity around the left deep inguinal ring via the inguinal canal to the subcutaneous space. The patient was diagnosed with HCN protruding into the abdominal cavity and extending to the subcutaneous space. Laparoscopy can easily access the hydrocele protruding into the abdominal cavity. Furthermore, laparoscopic hernioplasty can be superior to the anterior approach for females. Hence, laparoscopic surgery was performed. After transecting the round ligament of the uterus, a tense 3-cm hydrocele was dissected with it. In order to approach the hydrocele distal to the deep inguinal ring, the transversalis fascia was incised medially to the inferior epigastric vessels. The subcutaneously connected hydrocele was excised from the incision. Then, the enlarged deep inguinal ring was reinforced using a mesh with the laparoscopic transabdominal preperitoneal approach. The patient was discharged 2 days postoperatively. Laparoscopic resection can be more effective for a hydrocele protruding into the abdominal cavity as it facilitates an easy access to the hydrocele. Moreover, laparoscopic resection of a hydrocele extending from the inguinal canal to the subcutaneous space via a transversalis fascia incision can be safer, with low risk of injury to the inferior epigastric vessels. The incised transversalis fascia and the enlarged deep inguinal ring due to the HCN were simultaneously repaired with the laparoscopic transabdominal preperitoneal repair. There are two reports on laparoscopic resection via a transversalis fascia incision for HCNs located between the inguinal canal and the subcutaneous space, which does not require intraperitoneal hydrocelectomy. However, this is the first report on laparoscopic resection of large HCNs protruding into the abdominal cavity and extending beyond the inguinal canal into the subcutaneous space via intraperitoneal hydrocelectomy and a transversalis fascia incision. CONCLUSIONS: Laparoscopic surgery with transversalis fascia incision can be useful for HCNs extending from the abdominal cavity to the subcutaneous space.

BACKGROUND: Laparoscopic gastrectomy (LG) for remnant gastric cancer (RGC) remains controversial because of its rarity and heterogeneity of clinical characteristics. Based on our experience, we posited that our established methodology in LG could be applied to the laparoscopic procedure for RGC surgery and introduced LG for RGC at our institution in 2004. METHODS: This study enrolled 46 patients who underwent LG for RGC between January 2004 and December 2017. Data were obtained through a review of our prospectively maintained database. Laparoscopic total gastrectomy (LTG) was the standard surgical procedure for RGC. Laparoscopic subtotal gastrectomy (LsTG) was performed as an alternative procedure for patients with RGC located near the anastomotic site after primary gastrectomy. The technical and oncological feasibility and safety of LG for RGC were evaluated. RESULTS: LTG for RGC was performed on 36 patients. LsTG for RGC was performed on 10 patients. All patients completed LG procedure and succeeded R0 resection. Complications of Clavien-Dindo classification grade ≥ IIIa occurred in 4 (8.7%) patients. The retrospective video reviews showed that the time for adhesiotomy around the suprapancreatic area and the lesser curvature of the remnant stomach was significantly shorter in the primary-benign group than in the primary-malignant group. With the median follow-up period of 40 months, the 3-year recurrence-free survival and 3-year overall survival rates were 72.3% and 80.2%, respectively. CONCLUSION: LG for RGC represents a safe and feasible surgical option with favorable short-term and long-term outcomes in patients with RGC.

BACKGROUND: Systematic lymph node dissection in patients with gastric cancer could be sufficiently and reproducibly achieved along the outermost layer of the autonomic nerves and similar concept has been extensively used for robotic esophagectomy (RE) since 2018. This study aimed to determine the surgical and oncological safety of RE using the outermost layer-oriented approach for esophageal cancer (EC). METHODS: Sixty-six patients who underwent RE with total mediastinal lymphadenectomy for primary EC between April 2018 and December 2021 were retrospectively reviewed. All underwent the outermost layer-oriented approach with intraoperative nerve monitoring (IONM). Postoperative complications within 30 days were analyzed. RESULTS: Among the patients, 51 (77.3%) were male. The median age was 64 years, and the body mass index was 21.8 kg/m2. Furthermore, 58 (87.9%) patients had squamous cell carcinoma and eight (12.1%) patients had adenocarcinoma. Clinical stages I, II, and III were seen in 23 (34.8%), 23 (34.8%), and 16 (24.2%) patients, respectively. Thirty-four (51.5%) patients received preoperative treatment. No patient shifted to conventional thoracoscopic or open procedure intraoperatively. The median operative time was 716 min with 119 mL of blood loss. Additionally, 64 (97%) patients underwent R0 resection. The morbidity rates based on Clavien-Dindo grades ≥ II and ≥ IIIa were 30.3% and 10.6%, respectively, within 30 postoperative days. None died within 90 days postoperatively. Three (4.5%) patients exhibited recurrent laryngeal nerve (RLN) palsy (CD grade ≥ II). The sensitivity and specificity of IONM for RLN palsy were 50% and 98.3% at the right RLN and 33.3% and 98.0% at the left RLN, respectively. CONCLUSION: RE with the outermost layer-oriented approach can provide safe short-term outcomes.